As in all Slavic languages (except modern Bulgarian and Macedonian), many words (especially nouns, verbs, and adjectives) have many forms (inflections). In this regard, Czech and the Slavic languages are closer to their Indo-European origins than other languages in the same family that have lost much inflection. Moreover, in Czech the rules of morphology are extremely irregular and many forms have official, colloquial and sometimes semi-official variants. The word order serves similar function as emphasis and articles in English.
The phonology of Czech may also be very difficult for speakers of other languages. For example, some words do not appear to have vowels: zmrzl (froze to death), ztvrdl (hardened), scvrkl (shrunk), ctvrthrst (quarter-handful), blb (fool), vlk (wolf), and smrt (death). A popular example of this is the phrase "strc prst skrz krk" meaning "stick a finger through your throat" or "Smrž pln skvrn zvlhl z mlh." meaning "Morel full of spots wetted from fogs". The consonants l and r, however, function as sonorants and thus fulfill the role of a vowel (a similar phenomenon also occurs in American English, for example bird is pronounced as [brd] with a syllabic r).
In the Czech Republic three distinct koine, or interdialects can be found, all corresponding more or less to geographic areas within the country. They differ from standard Czech, creating some form of diglossia. The first, and most widely used, is "Common Czech", spoken in Bohemia. It has some grammatical differences from "standard" Czech, along with some differences in pronunciation. The most common pronunciation changes include -ý becoming -ej in some circumstances, -é becoming -ý- in some circumstances (-ej- in others), and the insertion of prothetic v- at the beginning of some words starting with o-. Also, noun declension is changed, most notably the instrumental case.
The second major interdialect is spoken in Moravia. This dialect has some totally different words from standard Czech. Unlike in Bohemia, Moravia tends to have more local dialects varying from town to town. For example in Brno, tramvaj (streetcar or tram) is šalina (originating from German "ElektriSCHELINIE"). Everyday spoken form in Moravia would be a mixture of given interdialect, remnants of old local dialect, some Standard Czech forms and sometimes also Common Czech.
The third major dialect - Teshen Silesian - is spoken in Silesia, centered around the city Ostrava. This dialect, too, is grammatically sound and closer to Standard Czech, but in this dialect people speak very quickly, and the long vowels become the same as their short counterparts.